Adjustable desk lamp



FIG. 1 is a front view of an adjustable desk lamp showing my new design;

FIG. 2 is a rear elevation view thereof;

FIG. 3 is a left elevation view thereof;

FIG. 4 is a right elevation view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a bottom plan view thereof; and,

FIG. 7 is a top perspective view thereof. 

The ornamental design for an adjustable desk lamp, as shown and described. 